Sub-surface water leaks: These occur when groundwater levels rise enough to enter the house through cracks or openings in foundations, basement slabs, or sumps and foundation drainage systems. You can prepare for this degree of basement flooding by raising the furnace, water heater, appliances, and storage items an adequate distance above the floor using waterproof blocking.
Spring run-off and minor surface flooding: During spring run-off or surface water flooding events, the amount of water in foundation drainage systems increases the demand on the sump pump system. Check the ejection pipe, sump and sump pump to be sure that they are functioning properly. If prolonged flooding or a power outage is possible, consider keeping a spare sump pump and a gas powered electric generator available. Store generator fuel safely and operate the generator in a safe location where exhaust fumes cannot enter the home.
Sewer back-ups: These can occur even if the blockage or flooding is some distance from your home. To protect your home, consider having a valve or one-way check valve installed where the sewer main leaves the house. A plumbing professional can help you determine the best method and location. If you do not have a valve installed to block the sewer main, temporary compression plugs can be inserted in floor drains and plumbing drain openings. Remember that a sewer system blockage could force water higher up in the home’s drainage system than expected.
Major surface flooding: When streams and rivers overflow their banks, major surface floods present the greatest threat of structural damage to the home. If the home is outside of areas protected by dikes, and the foundation has been strengthened or braced and sealed sufficiently to withstand the external water pressure, it may be possible to keep the basement dry using gas powered pumps. If the basement has not been reinforced and is incapable of withstanding the force of floodwaters, allowing the basement to fill with water may protect the foundation from structural damage by keeping the pressure similar on both sides of the foundation walls and floor.
If there is still time before the flooding, move stored items, furniture, and appliances to a safe upper level of the home or to a safe location outside the flood zone. Before the home is flooded, shut off the water, gas and electricity. After flooding clean-up and repairs, your utility company may require that service be restored only by trained utility representatives.
Citizens can access the most up-to-date information on flood preparation by visiting Extension’s website at www.extension.umn.edu/flood. Information about recovering from floods will be added as it becomes relevant.
Also available are Extension’s toll free phone services, the Flood Information Line (1-800-232-9077) and the AnswerLine (1-800-854-1678). Extension’s Flood Information Line is a resource for questions about water, crops, horticulture and climatology issues. Extension’s AnswerLine provides answers to household and family-oriented questions, such as cleaning, mildew, and food safety issues.